fs/file.c: replace get_unused_fd() with get_unused_fd_flags(0)

This patch replaces calls to get_unused_fd() with equivalent call to
get_unused_fd_flags(0) to preserve current behavor for existing code.

In a further patch, get_unused_fd() will be removed so that new code
start using get_unused_fd_flags(), with the hope O_CLOEXEC could be
used, either by default or choosen by userspace.
Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/file.c

@@ -869,7 +869,7 @@ SYSCALL_DEFINE1(dup, unsigned int, fildes)
 	struct file *file = fget_raw(fildes);
 
 	if (file) {
-		ret = get_unused_fd();
+		ret = get_unused_fd_flags(0);
 		if (ret >= 0)
 			fd_install(ret, file);
 		else